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recipe for cone 10 woo yellow

updated sun 17 jul 05

 

Vince Pitelka on sat 9 jul 05


> Vince, would you care to share the recipe for the Woo Yellow that you
> speak of. I attended a week at your facility last year but don't remember
> getting the recipe.

Fred -
Workshop participants often receive recipes for glazes, slips, or claybodies
specified by the workshop instructor, but this Woo Yellow is one of the
stock glazes we use in our BFA program during the academic year, so of
course a workshop participant wouldn't have received this recipe unless they
specifically asked for it.

Please note that this is a dry mat iron yellow, very beautiful, but obvously
not a stable glaze and completely unsuitable for ANY food contact surfaces.
It's beautiful dry yellow in reduction firing, and goes to brown where thin.
It also does nicely in salt and soda firing, where it comes out more of a
satin matt. I have never tried it without the zinc oxide. On a dry matt, I
would expect that the zinc would all burn out.

Woo Yellow - Cone 10
Kona F-4 Feldspar 35.9
Barium Carbonate 27.2
Zinc Oxide 16.3
Dolomite 13.0
EPK 8.0
Total 100.0
+ Red Iron Oxide 3.3%
Bentonite 2.2%

Ron Roy on sun 10 jul 05


Hi Vince and everyone,

A couple of comments - I found my old glaze book from college and tried to
look up Woo Yellow - I was mistaken I don't have it - I do have Kormans
Yellow and Lewis Yellow - and the Alfred glaze I think I used - with 20%
Barium. None of them had any zinc however.

I'm thinking you don't need that zinc if it's fired in reduction by the way
- it would be a good idea to test it without the zinc - zinc is an
expensive material.

With the zinc the silica and alumina is extremely low - with out it they
are still very low - so Vince is right - this is a very unstable glaze - If
I had to guess what amount of barium it would release into orange juice
over night I would say over 500 ppm. Love to know just how much.

Monona found some commercial cone 6 dinnerware once that released 3000 ppm
in a standard leach test.

She also quoted a Doctor Dr. Woodhall Stopford, the toxicologist for ACMI,
indicated to her in a letter that a ceramic cup that would leach 800 ppm
barium could be fatal to a child.

RR




>Workshop participants often receive recipes for glazes, slips, or claybodies
>specified by the workshop instructor, but this Woo Yellow is one of the
>stock glazes we use in our BFA program during the academic year, so of
>course a workshop participant wouldn't have received this recipe unless they
>specifically asked for it.
>
>Please note that this is a dry mat iron yellow, very beautiful, but obvously
>not a stable glaze and completely unsuitable for ANY food contact surfaces.
>It's beautiful dry yellow in reduction firing, and goes to brown where thin.
>It also does nicely in salt and soda firing, where it comes out more of a
>satin matt. I have never tried it without the zinc oxide. On a dry matt, I
>would expect that the zinc would all burn out.
>
>Woo Yellow - Cone 10
>Kona F-4 Feldspar 35.9
>Barium Carbonate 27.2
>Zinc Oxide 16.3
>Dolomite 13.0
>EPK 8.0
>Total 100.0
>+ Red Iron Oxide 3.3%
> Bentonite 2.2%

Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Phone: 613-475-9544
Fax: 613-475-3513

Daniel Semler on sat 16 jul 05


Hi Vince,

This could my attention and I had a slot in my glaze test schedule - ie. had
not prepared anything else.

I mixed up this and a version subbing SrCO3 for the BaCO3. I'll probably only
get partial results back by the time I leave to go to Oz for 3 wks, at the end
of July. Will report results when I get them though.

The sub version is below in case you are interested in trying it out.

Woo Yellow (SrO)
Code Number:
=========================================

F4 SPAR..................... 38.52
STRONT CARB................. 21.46
ZINC Oxide.................. 17.49
DOLOMITE.................... 13.95
EPK......................... 8.58
RED IRON OX................. 3.30
BENTONITE................... 2.20
=========
105.50

I thought this would be an interesting test of the similarity of barium and
strontium.

Thanx
D

Vince Pitelka on sat 16 jul 05


Daniel -
I'll look forward to hearing about the test results. In the mean time,
follow that Yellow Brick Road, don't be fooled by the Emerald Palace, and
watch out for flying monkeys -
- Vince

----- Original Message -----
From: "Daniel Semler"
To:
Sent: Saturday, July 16, 2005 5:05 PM
Subject: Re: Recipe for cone 10 Woo Yellow


> Hi Vince,
>
> This could my attention and I had a slot in my glaze test schedule - ie.
> had
> not prepared anything else.
>
> I mixed up this and a version subbing SrCO3 for the BaCO3. I'll probably
> only
> get partial results back by the time I leave to go to Oz for 3 wks, at the
> end
> of July. Will report results when I get them though.
>
> The sub version is below in case you are interested in trying it out.
>
> Woo Yellow (SrO)
> Code Number:
> =========================================
>
> F4 SPAR..................... 38.52
> STRONT CARB................. 21.46
> ZINC Oxide.................. 17.49
> DOLOMITE.................... 13.95
> EPK......................... 8.58
> RED IRON OX................. 3.30
> BENTONITE................... 2.20
> =========
> 105.50
>
> I thought this would be an interesting test of the similarity of barium
> and
> strontium.
>
> Thanx
> D
>
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